1. Field of the Invention
The present invention relates to a zoom optical system and an imaging apparatus using the zoom optical system.
2. Description of the Related Art
A conventional zoom optical system is formed of a variator group having a magnification varying function, a compensator group for compensating for shift of an image surface and aberrations caused by magnification change, and a focusing group for focusing onto an object. Also, the zoom optical system is configured to perform magnification change and focusing by moving, of the above described lens groups, predetermined lens groups in the direction of the optical axis.
Also, in recent years, imaging apparatuses using high-resolution zoom optical systems have been required. For example, each of Japanese Patent Application Preliminary Publication (KOKAI) No. Hei 8-248318 and Japanese patent Application Preliminary Publication (KOKAI) No. 11-220646 discloses an imaging apparatus using a zoom optical system that achieves compact design by folding the path of rays.